Many designs for golf tees exist. Those that are acceptable for use in competition golf matches comprise a shaft section with a point for inserting the tee into the ground and a head or cup component for holding the golf ball. The nature of the shaft design is critical in providing a tee that is easily inserted into the ground with minimal force, but good holding power in all soil conditions. The head geometry has to provide a location point for the golf ball and allow for easy removal during the driving shot with no adverse effect on the direction and trajectory of the golf ball.
U.S. Design Pat. No. 502,972, published Mar. 15, 2005, describes a conventional tapered circular shaft design with a head having four raised portions that provide contact points for supporting the golf tee. The design shown has a very substantial shaft cross-section making it potentially difficult to drive into heavy ground. The mass of the golf tee is also likely to be substantial, potentially making the tee relatively expensive.
U.S. Design Pat. No. 501,902, published Feb. 15, 2005, describes a circular headed golf tee with a cylindrical shaft having a slight taper and then converging to a point at the very end of the shaft. The head portion of the tee is relative thick and large with an external depth approximately 15-20% the total length of the shaft. Six small shallow fluted chamfers stopped at both ends have been introduced to the underside of the head, presumably to reduce some of the mass from this heavy mass portion of the tee. The tapered cylindrical shaft also has three small shallow fluted chamfers stopped at the underside of the tee head and at the shaft pointed section of the shaft.
U.S. Pat. No. 6,849,001, published Feb. 1, 2005, describes a golf tee comprising a peg member for insertion into the ground and a flexible holding member for locating the seat portion for the golf ball to the peg. Whilst the performance of the driving action may be improved by adjusting the position of the seat portion, the design is highly complex making it uneconomic for normal golf activities.
In U.S. Design Pat. No. 491,619, published Jun. 15, 2004, a golf tee contains a golf ball supporting structure comprising 12 circular groups of fibers located around the outer circumference of a round head. A conventional cylindrical shaft is fitted to the lower portion of the tee head.
In U.S. Design Pat. No. 492,743, published Jun. 6, 2004, a tee has a conventional tapered cylindrical shaft, however the head is shaped like an inverted hollow truncated cone with the truncated point attached to the shaft. Four sections from the sides of the truncated cone shaped head have been removed presumably to reduce mass. The top of the tee head that is in contact with the golf ball has four very small protruding dimples to provide small contact points with the golf ball. The location of the four dimples is in the form of an isosceles trapezoid. The form of this golf tee would be extremely difficult to mass-produce, thus making it less commercially viable.
U.S. Design Pat. No. 488,525, published Apr. 13, 2004, describes a golf tee with three points arranged in a triangular array as the location point for the golf tee. The drawing in said application appears to indicate that the pointed head is carved from the thicker portion of the cylindrical shaft. This design would be expensive and extremely difficult to replicate for a large volume market such as commercial golf tees.
U.S. Design Pat. No. 485,591, published Jan. 20, 2004, describes a circular head with a hemispherical depression. The shaft is essentially square in cross section with a very slight taper along the main length of the shaft before tapering to a point. It is clear that the head of the tee provides continuous contact with a golf ball around the entire circumference of the tee head and in the depression of the head. The geometry of the golf tee head and shaft show no apparent benefits in improving the holding capability or driving capability of a golf ball.
None of the above patent applications describe a golf tee which meets all the current requirements of low cost production, low mass, good penetration into the ground under all conditions and the ability to balance a golf ball on the head component with minimal contact area.